Appearance: Jack stands about 6'3", well built, with dark hair and green eyes. His skin tone is slightly pale, due to his Irish decent, and he has worn glasses since he was 10.
Background: He grew up in lower Manhattan as the son of the late Detective Brendan Harper, who was killed in a driveby - possibly mob related - shooting while out with his son, when Jack was 13. There was no mother in the equation; she left when he was too young to really remember. Jack's father was a harsh man, because he didn't know any other way to raise his son other than the techniques that went on at work. From an early age, Jack was held to his father's tall standards, and he learned quickly not to fail his father.
When Brendan died, Jack had no family, so he was taken in by Mark Stettner and his family - who was a friend of his father. Mark's son David, and Jack, became brothers and still stay in contact today (which sometimes is especially useful since David Stettner is now a doctor).
Jack graduated high school near the top percent of his class, but not at the very highest. He tried to join the Marines at the age of 18, but didn't quite make the cut due to being born with asthma. Instead, he went to the next best thing - the police academy. Once Jack became a cop, he continued to take classes, usually criminology, law or pyschology related, at night school. He walked a beat for five years before being accepted to becoming a detective.
In the detectives bureau, his first job was a brief two year stint in computer crimes. He wasn't perticularly happy there, and when there was a chance to transfer elsewhere, Jack took a placement in narcotics for four years. While narco kept him busy - which was what Jack wanted - his true goal was to be in homicide, like his father. At the end of his fourth year in narco, he was finally transferred to homicide for three under Captain Max White, who had known Brendan when he was alive.
Jack proved to be a good homicide investigator, but somewhat due to his past, he found that some of the cases pushed him a little too close to the edge. He had been cited a few times for unnessicary violence, and there were a few cases of impaired judgement on his part. During his course in homicide, he lost a partner on the job, and this became the final straw. Captain White, while he liked Harper and thought that he was a good cop, figured that homicide was not the best place for him, especially after his partner died, and pulled a few strings with his friend Don Cragen, getting Jack a place in SVU.
Currently, he is beginning his second year in the Special Victims Unit.
Personality: Jack is usually a quiet, withdrawn man. During a case, he is calm, but not uncaring. However, he does have several quick triggers that will release an Irish temper that has been pent up since he was very young, dealing with the issues in his childhood. Inwardly, Jack is an angry man. He doesn't do well with relationships with girlfriends, and they generally don't last long. He continues to think that life has delt him a loosing hand over and over and the reason is probably something that was his fault. He doesn't like people becoming too close to him, afraid that he'll loose them again. For all of that though, he does have some sense of humor, though often it is more dark than anything else. For Jack, humor can sometimes be his escape.
Quirks/Weaknesses/Flaws: Jack was born with asthma, which is part of the reason that kept him out of the Marines, but it wasn't bad enough to keep him from the police department too. He also has a bad temper at times, and a cynical additude that comes forward if and when he does voice his opinion.